#include <signal.h>
#include <stdio.h>

static void sig_usr(int);

static void  sig_alarm(int signo){
	
}

int main(){
	if(signal(SIGUSR1,sig_usr)==SIG_ERR){
		fprintf(stderr,"can't catch SIGUSR1\n");
	}
	
	signal(SIGALRM,sig_alarm);
	
	alarm(1);	
	for(;;)
		pause();
}

static void sig_usr(int signo){
	if(signo==SIGUSR1){
		printf("received SIGUSR1\n");
	}else{
		printf("received signal %d\n",signo);
	}
}
